一段英文翻译成中文:InmostcountriesaPhDisabasicrequirementforacareerinacademia.Itisanintroductiontotheworldofindependentresearch––akindofintellectualmasterpiece,createdbyanapprenticeinclosecollaborationwithasupervisor.Therequirementstocompleteonevaryenormouslybetweencountries,universitiesandevensubjects.